Field
Aspects of the present invention generally relate to a light source device and a projection display apparatus including the light source device.
Description of the Related Art
A projection display apparatus (projector) includes a light source device including light sources (light emitting diodes (LEDs), lasers, or lamps) for red (R), green (G), and blue (B). In such a light source device, when a light source emits light, the temperature of the light source increases.
If the temperature of a light source becomes excessively high, the lifetime of the light source can be shortened. Further, in the case where an LED is used as a light source, a rise in the temperature of the LED leads to a decrease in the amount of output light of the LED because LEDs have a sensitive light-amount characteristic with respect to the temperature. This leads to a decrease in the amount of light and a change in hues of a projection image, which leads to deterioration in image quality of the projection image. To address this, cooling mechanisms of light source devices have been discussed.
U.S. Pat. No. 8,562,143 discusses a configuration of a projection display apparatus including a plurality of light source devices for respective colors and a plurality of fans respectively corresponding to the plurality of light source devices. In this configuration, a fan and an airflow are provided to each of the light source devices. This results in an increase in the number of fans, which leads to an increase in the size of the cooling configuration.
Japanese Patent Application Laid-Open No. 2007-133300 discusses a projection display apparatus including a plurality of light source devices for respective colors and radiators (or heat pipes) respectively corresponding to the plurality of light source devices. In the configuration of the projection display apparatus discussed therein, the radiators are cooled with a single cooling fan. In this configuration, a radiator is provided to each of the light source devices, and the radiators are located separate from each other. Thus, the airflow becomes complicated, leading to frequent pressure losses, and it is difficult to realize efficiently cooling with a single cooling fan.